Bicycle frame



FIG. 1 is a right side view of a bicycle frame showing my new design, the portions of the bicycle shown in broken lines are for illustrative purposes only and form no part of the claimed design;

FIG. 2 is a top view of the bicycle frame;

FIG. 3 is a bottom view of the bicycle frame;

FIG. 4 is a left side view of the bicycle frame;

FIG. 5 is a front view of the bicycle frame; and,

FIG. 6 is a rear view of the bicycle frame. 

The ornamental design for a bicycle frame, as shown and described. 